6D30.10 - Newton's Rings
Demonstrate Newton's rings.
A concave lens is fixed against a glass plate in a special fixture which is mounted on a stand. The resulting reflected fringe pattern is projected on the side screen for the whole class to see. The face of the fixture is strongly illuminated with the light from the slide projector. The fixture is adjusted so that the bright spot from the reflection is on the side screen. Then a short focal length lens is inserted in the path so as to produce an image on the screen.